Maybe earnings are worth mentioning in an article like this? The advice is good, but not really quantifiable. OKCupid and Mint blog posts are a good example of how to convey information with real numbers.

For rough earnings, just look at the graphs in the post (units sold) and multiple it by the unit price for that time period. During the first graph (Apple Featured), the app was selling for $4.99. During the second graph (Daring Fireball), the app was selling for $9.99.

> ...find that people who rate free apps tend to be the harshest of all, as there is zero cost to participate.

Judging from my own experience this is true for ad supported apps only. If the app has no ads, it tends to get fewer negative reviews if any at all. I guess people feel less duped when they realize the developer didn't get anything to himself at their expense.

I just released an app on the Windows Phone 7 marketplace and some similar experiences in part. Especially the comments about "Release Early, Release Often".

For the first month after release some of the negative reviews were essentially feature requests. It certainly made me think that my MVP was maybe a little too minimum.

I plan to do a full summary in the next few months after the next version.

He makes an excellent point about being first to market - being first isn't great if you don't have a decent product to sell. Chinese knockoffs often show us how well that works in the real world. Aside from that though, the most important thing that he's shown is that getting sales is a constant struggle. You aren't magically going to become, and more importantly stay, popular overnight. A featured app slot is wonderful, but there's still a lot of work to be done even after something like that happens.